/* * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* $NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $ */ /* * SVID compatible sem.h file * * Author: Daniel Boulet * John Bellardo modified the implementation for Darwin. 12/2000 */ #ifndef _SYS_SEM_H_ #define _SYS_SEM_H_ #include <sys/cdefs.h> #include <sys/_types.h> /* * [XSI] All of the symbols from <sys/ipc.h> SHALL be defined * when this header is included */ #include <sys/ipc.h> /* * [XSI] The pid_t, time_t, key_t, and size_t types shall be defined as * described in <sys/types.h>. * * NOTE: The definition of the key_t type is implicit from the * inclusion of <sys/ipc.h> */ #ifndef _PID_T typedef __darwin_pid_t pid_t; #define _PID_T #endif #ifndef _TIME_T #define _TIME_T typedef __darwin_time_t time_t; #endif #ifndef _SIZE_T #define _SIZE_T typedef __darwin_size_t size_t; #endif /* * Technically, we should force all code references to the new structure * definition, not in just the standards conformance case, and leave the * legacy interface there for binary compatibility only. Currently, we * are only forcing this for programs requesting standards conformance. */ #if defined(__POSIX_C_SOURCE) || defined(kernel) || defined(__LP64__) /* * Structure used internally. * * This structure is exposed because standards dictate that it is used as * the semun union member 'buf' as the fourth argment to semctl() when the * third argument is IPC_STAT or IPC_SET. * * Note: only the fields sem_perm, sem_nsems, sem_otime, and sem_ctime * are meaningful in user space. */ struct __semid_ds_new { struct __ipc_perm_new sem_perm; /* [XSI] operation permission struct */ __int32_t sem_base; /* 32 bit base ptr for semaphore set */ unsigned short sem_nsems; /* [XSI] number of sems in set */ time_t sem_otime; /* [XSI] last operation time */ __int32_t sem_pad1; /* RESERVED: DO NOT USE! */ time_t sem_ctime; /* [XSI] last change time */ /* Times measured in secs since */ /* 00:00:00 GMT, Jan. 1, 1970 */ __int32_t sem_pad2; /* RESERVED: DO NOT USE! */ __int32_t sem_pad3[4]; /* RESERVED: DO NOT USE! */ }; #define semid_ds __semid_ds_new #else /* !_POSIX_C_SOURCE */ #define semid_ds __semid_ds_old #endif /* !_POSIX_C_SOURCE */ #if !defined(__POSIX_C_SOURCE) && !defined(__LP64__) struct __semid_ds_old { struct __ipc_perm_old sem_perm; /* [XSI] operation permission struct */ __int32_t sem_base; /* 32 bit base ptr for semaphore set */ unsigned short sem_nsems; /* [XSI] number of sems in set */ time_t sem_otime; /* [XSI] last operation time */ __int32_t sem_pad1; /* RESERVED: DO NOT USE! */ time_t sem_ctime; /* [XSI] last change time */ /* Times measured in secs since */ /* 00:00:00 GMT, Jan. 1, 1970 */ __int32_t sem_pad2; /* RESERVED: DO NOT USE! */ __int32_t sem_pad3[4]; /* RESERVED: DO NOT USE! */ }; #endif /* !_POSIX_C_SOURCE */ /* * Possible values for the third argument to semctl() */ #define GETNCNT 3 /* [XSI] Return the value of semncnt {READ} */ #define GETPID 4 /* [XSI] Return the value of sempid {READ} */ #define GETVAL 5 /* [XSI] Return the value of semval {READ} */ #define GETALL 6 /* [XSI] Return semvals into arg.array {READ} */ #define GETZCNT 7 /* [XSI] Return the value of semzcnt {READ} */ #define SETVAL 8 /* [XSI] Set the value of semval to arg.val {ALTER} */ #define SETALL 9 /* [XSI] Set semvals from arg.array {ALTER} */ /* A semaphore; this is an anonymous structure, not for external use */ struct sem { unsigned short semval; /* semaphore value */ pid_t sempid; /* pid of last operation */ unsigned short semncnt; /* # awaiting semval > cval */ unsigned short semzcnt; /* # awaiting semval == 0 */ }; /* * Structure of array element for second argument to semop() */ struct sembuf { unsigned short sem_num; /* [XSI] semaphore # */ short sem_op; /* [XSI] semaphore operation */ short sem_flg; /* [XSI] operation flags */ }; /* * Possible flag values for sem_flg */ #define SEM_UNDO 010000 /* [XSI] Set up adjust on exit entry */ #ifndef _POSIX_C_SOURCE /* * System imposed limit on the value of the third parameter to semop(). * This is arbitrary, and the standards unfortunately do not provide a * way for user applications to retrieve this value (e.g. via sysconf() * or from a manifest value in <unistd.h>). The value shown here is * informational, and subject to change in future revisions. */ #define MAX_SOPS 5 /* maximum # of sembuf's per semop call */ /* * Union used as the fourth argment to semctl() in all cases. Specific * member values are used for different values of the third parameter: * * Command Member * ------------------------------------------- ------ * GETALL, SETALL array * SETVAL val * IPC_STAT, IPC_SET buf * * The union definition is intended to be defined by the user application * in conforming applications; it is provided here for two reasons: * * 1) Historical source compatability for non-conforming applications * expecting this header to declare the union type on their behalf * * 2) Documentation; specifically, 64 bit applications that do not pass * this structure for 'val', or, alternately, a 64 bit type, will * not function correctly */ union semun { int val; /* value for SETVAL */ struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */ unsigned short *array; /* array for GETALL & SETALL */ }; typedef union semun semun_t; /* * Permissions */ #define SEM_A 0200 /* alter permission */ #define SEM_R 0400 /* read permission */ #endif /* !_POSIX_C_SOURCE */ #ifndef KERNEL __BEGIN_DECLS #ifndef _POSIX_C_SOURCE int semsys(int, ...); #endif /* !_POSIX_C_SOURCE */ int semctl(int, int, int, ...) __DARWIN_ALIAS(semctl); int semget(key_t, int, int); int semop(int, struct sembuf *, size_t); __END_DECLS #endif /* !KERNEL */ #endif /* !_SEM_H_ */